Amazon.com revived speculation about its next major product earlier this month, using a mysterious YouTube video and website post to announce a June 18 “launch event” in Seattle to be hosted by Chief Executive Jeff Bezos.

The Journal and several tech blogs have reported that the internet retailer may be working on a phone with a three-dimensional display.

Rumors of an Amazon-designed smartphone have circulated for years, though executives have played down ambitions to leap into a heavily competitive and increasingly saturated market dominated by Apple Inc and Samsung Electronics Co Ltd .

AT&T was the exclusive partner of Apple Inc when it launched the iPhone in 2007.

AT&T declined to comment, while Amazon could not be reached immediately.

Shares of both companies were little changed in premarket trading on Tuesday

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